The IPv6 (Internet Protocol Version 6, Internet protocol version 6) technology has been increasingly mature, and has more and more applications. Meanwhile, IPv4 (Internet Protocol Version 4, Internet protocol version 4) addresses available for allocation are increasingly diminishing, evolution to IPv6 supported by a mobile broadband network is imperative.
After a PS (Packet Switch, packet switch) domain core network of the mobile broadband network evolves to the IPv6, for example, after a data transmission interface between an SGSN (Serving GPRS Support Node, serving general packet radio service support node) and an S-GW (Serving Gateway, serving gateway), a data transmission interface between an MME (Mobility Management Entity, mobility management entity) and an SGSN, a data transmission interface between an S-GW and an RNC (Radio Network Controller, radio network controller), and a data transmission interface between an S-GW and an eNodeB (Evolved Node B, evolved Node B) all support IPv6 transmission, GTP (GPRS Tunneling Protocol, general packet radio service tunneling protocol) has to be borne on UDP (User Datagram Protocol, user datagram protocol) of the IPv6, and a checksum must be calculated for all GTP packets on a control plane and a user plane. The checksum calculation of the UDP includes checksum calculation of a UDP header and checksum calculation of a UDP load. The checksum of the UDP is calculated by a sending end, and then verified by a receiving end, and if the receiving end detects that the checksum has an error, a GTP packet has to be discarded. In some situations, the cost of discarding the packet is very large, especially for services having large packets such as audios or videos. Performing the checksum calculation of the UDP on services having a better packet error resilient such as audios or videos significantly reduces data transmission efficiency.